1 /* 2 * Copyright (c) 1980, 1988 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 char copyright[] = 36 "@(#) Copyright (c) 1980, 1988 The Regents of the University of California.\n\ 37 All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 /*static char sccsid[] = "from: @(#)from.c 5.7 (Berkeley) 3/1/91";*/ 42 static char rcsid[] = "$Id: from.c,v 1.5 1994/11/24 14:53:10 deraadt Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <ctype.h> 47 #include <pwd.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <unistd.h> 51 #include <paths.h> 52 53 main(argc, argv) 54 int argc; 55 char **argv; 56 { 57 extern char *optarg; 58 extern int optind; 59 struct passwd *pwd; 60 int ch, newline; 61 char *file, *sender, *p; 62 #if MAXPATHLEN > BUFSIZ 63 char buf[MAXPATHLEN]; 64 #else 65 char buf[BUFSIZ]; 66 #endif 67 68 file = sender = NULL; 69 while ((ch = getopt(argc, argv, "f:s:")) != EOF) 70 switch((char)ch) { 71 case 'f': 72 file = optarg; 73 break; 74 case 's': 75 sender = optarg; 76 for (p = sender; *p; ++p) 77 if (isupper(*p)) 78 *p = tolower(*p); 79 break; 80 case '?': 81 default: 82 fprintf(stderr, "usage: from [-f file] [-s sender] [user]\n"); 83 exit(1); 84 } 85 argv += optind; 86 87 /* 88 * We find the mailbox by: 89 * 1 -f flag 90 * 2 user 91 * 2 MAIL environment variable 92 * 3 _PATH_MAILDIR/file 93 */ 94 if (!file) { 95 if (!(file = *argv)) { 96 if (!(file = getenv("MAIL"))) { 97 if (!(pwd = getpwuid(getuid()))) { 98 (void)fprintf(stderr, 99 "from: no password file entry for you.\n"); 100 exit(1); 101 } 102 if (file = getenv("USER")) { 103 (void)sprintf(buf, "%s/%s", 104 _PATH_MAILDIR, file); 105 file = buf; 106 } else 107 (void)sprintf(file = buf, "%s/%s", 108 _PATH_MAILDIR, pwd->pw_name); 109 } 110 } else { 111 (void)sprintf(buf, "%s/%s", _PATH_MAILDIR, file); 112 file = buf; 113 } 114 } 115 if (!freopen(file, "r", stdin)) { 116 (void)fprintf(stderr, "from: can't read %s.\n", file); 117 exit(1); 118 } 119 for (newline = 1; fgets(buf, sizeof(buf), stdin);) { 120 if (*buf == '\n') { 121 newline = 1; 122 continue; 123 } 124 if (newline && !strncmp(buf, "From ", 5) && 125 (!sender || match(buf + 5, sender))) 126 printf("%s", buf); 127 newline = 0; 128 } 129 exit(0); 130 } 131 132 match(line, sender) 133 register char *line, *sender; 134 { 135 register char ch, pch, first, *p, *t; 136 137 for (first = *sender++;;) { 138 if (isspace(ch = *line)) 139 return(0); 140 ++line; 141 if (isupper(ch)) 142 ch = tolower(ch); 143 if (ch != first) 144 continue; 145 for (p = sender, t = line;;) { 146 if (!(pch = *p++)) 147 return(1); 148 if (isupper(ch = *t++)) 149 ch = tolower(ch); 150 if (ch != pch) 151 break; 152 } 153 } 154 /* NOTREACHED */ 155 } 156